Safely bring back the robot to home position

[Robotic5]

Is it possible when you are executing a program en this stops (by whatever) to the robot safely back to the homeposition?
It's an ABB IRB6400

[Fabian Munoz]

The question is good for any robot.

Depending on the application it could be very simple or very hard, but, of course it's possible.


Myself, I hate to do that. There are many many conditions to be satisfied to send a robot Home from wherever it is, but like I said before, on some applications is very easy.

One thing  that,s very important and that for me is rule NUMBER ONE.

You can send the robot back home  or maintenance or purge, etc  AS LONG AS THE YOU KEEP THE ROBOT IN AUTO MODE. Once you go on teach, youo should not trust where the robot is positioning

[Robotic5]

I understand but my problem is how?
Because in our situation the robot is moving between multiple objects.
And when i simply send the robot to homeposition, then he hits things in it's way.

[Fabian Munoz]

I dont remember  from the top of my head how to interrupt/abort/stop a job on ABB.

Tyhe general procedures to retrieve the robot will be:

After every point you have a routine to go home
Example, every letter is a point

Home

a
move Home if necessary

b
move a,Home if necessary

c
move b, a,Home if necessary

and on.


You can achieve this writing different routines where you have all the backsteps or just directly the back steps if a condition happens

Obviously, this gets complicacted when you are manipulating, etc. because the conditions in and out are different.  Yuo could have a part on the gripper for example and  there's no room to move backwards with the part.

If my answer doesnt give an idea write again. Be very specific

[tony gast]

I work with many different robot types and am not an ABB expert....that being said.....
TRAPs I think is what you write to abort to another module.....and as somar states.....writing the return to home may be simple or difficult depending on how you got to the location you want to go home from.....
I have written programs that look at the joint positions and figured where the tool was in XYZ to go up and over obstacles(or using cubes to do the same thing). and I have written programs that record paths as the robot moves forward(into variables) to allow the robot to back out from any positions.....

[Android]

Yes. Its possible in IRC5.

But you need to have options like store path and etc in Motion Advanced Instruction list in Flex pendant.

So dat you can store the path.. using storepath instruction.
You can move the robot backward using stepbackwardpath instruction.
In starting of the program use clearpath instruction.

If you have the above options, Its 4 hr job to complete this job.. If not you need to buy dem from ABB..

Good Luck..

[spaceacealpha]

On your IRB6400, If you have a 'clear' ceiling.

    TempPos:=CRobT();
    TempHgt:=CPos();
    IF TempHgt.z<750 THEN
      TempPos:=Offs(TempPos,0,0,750);
      MoveJ TempPos,Slow,z100,Gripper;
    ENDIF
    MoveJ Home_Pos,Slow,z200,Gripper;


(750 being the tallest object you need to dodge)
You can get fancy with this too, you can track your x and y positions and give special move commands. 

I've also on Fanuc's KAREL called up the actual position, compared joint 1,2 and 3 to all positions joints values for 1,2 and 3, give a score based on how close the joint is and the highest scoring position wins and the robot moves to this and then follows typical paths to home.  I don't have that code with me though and its less predictable than the above code.

[MotorCitySTI]

On your IRB6400, If you have a 'clear' ceiling.

    TempPos:=CRobT();
    TempHgt:=CPos();
    IF TempHgt.z<750 THEN
      TempPos:=Offs(TempPos,0,0,750);
      MoveJ TempPos,Slow,z100,Gripper;
    ENDIF
    MoveJ Home_Pos,Slow,z200,Gripper;


(750 being the tallest object you need to dodge)
You can get fancy with this too, you can track your x and y positions and give special move commands. 

I've also on Fanuc's KAREL called up the actual position, compared joint 1,2 and 3 to all positions joints values for 1,2 and 3, give a score based on how close the joint is and the highest scoring position wins and the robot moves to this and then follows typical paths to home.  I don't have that code with me though and its less predictable than the above code.

This " TempPos:=Offs(TempPos,0,0,750);" code will cause the robot the robot to go up an additionial 750 mm from where it is currently located.

I suggest

!Data
Const num nSafeHomeHeight:=750;
PERS robtarget pCurrentPos:=[[-765.706,75.8629,1100],[0.827152,-0.000301007,-0.561776,-0.0151286],[0,-1,0,4],[9E+09,9E+09,9E+09,9E+09,9E+09,9E+09]];



   !
   ! Get Home
   !
   pCurrentPos:=CRobT(\Tool:=tCurrentTool\WObj:=wobj0);
   !
   IF pCurrentPos.trans.z>=nSafeHomeHeight THEN
      !
      ! Robot is above nSafeHomeHeight Position going Home
      !
      TPErase;
      TPWrite " ";
      TPWrite " Robot above "\Num:=nSafeHomeHeight;
      TPWrite " Returning to Home position";
      !
      WaitTime 1;
      !
      MovetoHome;
      !
  ELSE
      !
      pCurrentPos.trans.z:=nSafeHomeHeight;
      MoveL pCurrentPos,v200,fine,toolGrip;     
      !
   ENDIF

There are a million ways to do this, depending on what options you have.

Jeremy